This invention relates to a mining apparatus and method and, more particularly, to an apparatus for mining reef bearing mineral such as platinum and gold and to a mechanised method for the removal thereof.
Hard rock mining techniques currently in use require a substantial labour force and often involve blasting of the rock face in order to expose the reef to allow the work force to then recover the mineral from the reef. Once the reef has been exposed, the mineral may for example be removed by further drilling and blasting, or an impact ripping operation which involves a hydraulically operated hammer which is applied manually to the face in order to break the rock which is then loaded onto a reciprocating conveyor which removes the rock from the face to a remote location for further processing.
Such operations are expensive, time and labour intensive. This leads to instances where ore may not be mined due to concerns as to the economic viability of the operation.
It is an object of the present invention to provide a mining system which can remove the reef both effectively and efficiently from such locations in order to make such operations economically feasible.
It is a further object of the present invention to provide a mining system and a method of mining that allows a greater recovery rate of mineral from a reef than is currently available. This is especially desirably in the mining of mineral from relatively small reefs such as around 800 mm in height.
According to one aspect of the present invention there is provided a mining machine for removing a reef of mineral from a rock face, the mining machine comprising a first cutting disc rotatably mounted on one side thereof, which disc is adapted to remove a portion of the rock face as the machine is traversed along the face; a second cutting disc rotatably mounted on the machine, at a position off-set from the first disc, and a cutting drum, said drum being mounted upon an arm which is vertically repositionable to allow the cutting drum to remove rock from the roof and floor of the trench formed by the action of the cutting discs.
An advantage of the above mining machine is that as the cutting discs remove the center portion of the seam of ore, the cutting drum follows and trims the remaining reef thereby creating a smooth roof and floor on which to allow the full system to advance freely.
Furthermore, as the position of the arm upon which the cutter drum is mounted can be adjusted vertically, the path of the drum can be altered to follow the contours of the reef and thereby recover additional material which cannot be recovered through use of an apparatus provided with the cutting discs alone.
Preferably the system further comprises a conveyor for the purpose of carrying the machine and a means for removing material from the rock face more advantageously a flexible conveyor.
Preferably also, the cutter drum comprises means to direct material cut from the face onto the conveyor means, thereby allowing the machine to be operated by a sole operator
Advantageously, means are provided for advancing the mining machine towards the rock face at the end of each pass along the face.
According to a further aspect of the present invention there is provided a mechanised method of removing mineral from a reef in a rock face, for example, using the system of the first aspect, which method comprises the steps of applying a cutting machine to the rock face, the cutting machine having a plurality of off-set cutting discs which remove the center part of the reef to form a channel, and applying a further cutting drum to the roof and floor of the channel which is cut into the mineral bearing reef to allow the system to advance freely. The further cutting drum may create a smooth roof and floor on which to allow the system to advance freely.